Method and apparatus for the manufacture of a spiral



Jan. 10, 1939. w. J. PODBIELNIAK 2,143,451

METHOD AND APPARATUS FOR THE MANUFACTURE OF A SPIRAL Filed June 25, 1936 2 Sheets-Sheet 1 Jan. 10, 1939. w. J. PODBIELNIAK 2,143,451

METHOD 'AND APPARATUS FOR THE MANUFACTURE OF A SPIRAL Filed June 25, 1936 2 Sheets-Sheet 2 r 20 streams.

Patented Jan. 10,- 1939 UNITED STATES PATENT org es METHOIJAND APPARATUS FORTHE MAN- UFACTURE OF A SPIRAL Walter J. Podbielniak, Chicago, n1. Application June 25, 1936, Serial No. 87,221

; I lit-Claims. (01.153-64 This invention relates to a method and apparatus for the manufacture of a'spiral sheet having a spiral passageway and more particularly to a spiral sheet for use in a rotor through which 5 fluids are caused totravel counter-currently in the spiral passageway due to centrifugalforce set up by the rapid rotation of the rotor.

In my prior application directed to the art of Securing. contact between fluids, Serial No.

.10 5,059,-flled February 5, 1935 patentedSeptember vided with spirally wound sheets to form a spiral I passageway through which the fluids pass counter-currently in continuous In. accordance with my invention I provide a novel a paratus and method for constructing these spiral sheets which is simple in design and construction and which-is capable of ready ma-' 35 rotor casing and aillxed thereinin the desired position. .This is accomplished by filling the spiral passageway of the spirally wound sheet while it is retained in the aforementioned apparatus, with a liquefied thermo-plas'tic material 40 such as waxand then permitting the wax to harden. The hardened or set wax. serves to maintain the desired relationship of the windings of the spiral and canbe readily removed from the spiral after it is installed in the rotor. 45 The apparatus employed by me and the process for making the spiralwill be readily understood from the following description taken in conjunction with the accompanying drawings, which form a part of my'speciflcation and in which: 50' Figure 1 is a plan view with parts removed and broken away of an app ratus embodying my invention in which a metal sheet has been wound into a spiral of the desired pitch;

Fig. 2 is a transverse sectional view thereof 5 taken along the line {-1 of Fig. 1;

uninterrupted Fig. 3 is a transverse sectional view thereof takenalong the line 3-4 of Fig. 1, shown with parts telescoped; and

Fig. 4 is an enlarged-fragmentary detail view, with parts in section, of a novel engaging device 5 utilized in an apparatus embodying my invention.

Referring more particularly to Figs. 1 to 3 of the drawings, I have shown a spirally wound sheet III of predetermined pitch retained in its wound form by a retention apparatus and having the connecting spaces between the successive turns I l of the spiral fllled with a suitable ther mopiastic material I 2.

The retention apparatus comprises an upper clamping plate or spider l3, and a lower spaced groove plate I l. The opposed faces of spider l3 and groove plate l4 .may be suitably provided with centrally located opposed recesses l5 and I6 respectively into which the ends of a tubular spacer I1 is retained. The spacer l1 servesto maintain a substantially fixed spaced relationship between. the spider l3 and the groove plate It and its length may be varied as the width of the sheet to be spirally wound varies. The spider I3, the groove plate 14 and the tubular spacer I! are assembled and retained in a unitary structure as by a central assembly bolt l8- having a screw-threaded tightening nut l9 at one extrem ity thereof.

From an 'inspection of Figs. 2 and 4 it is ap-. parent that the lower edges of the spirally wound sheet lb are retained in a spiral groove 20 formed in the upper face of the plate I4 and the upper edges of the sheet are rigidly engaged as by 5 slotted pins 2|, forming part of an engaging device 22, which pass through the legs 21 of spider l3 to engage them free edges.

As statedabove, the lower groove plate I! is provided with a spiral groove 20. This groove 40 is formed in a spiral having a predetermined pitch between the successive turns of the groove and may be preferably so designed that it will at least temporarily retain the wound sheet In in its spiral .form independently of other retention means. V

To accomplish this, groove. 20 is formed with a substantially V-shapein which the bottom 23 is preferably flat and has a width less than the width of the month. 'As is readily apparent from Fig. 2,'the walls 24 and 2!: of the grooves slope away from theaais of rotation. The outer wall 25 of the groove, makes anangle of substantially 10 more or less, with a line drawn. parallel to the axis of plate ll. Consequently, the outer wall I! the sheet first contacts the inner wall 24 of the groove; and as the pressure is continued, the lower edge is urged to the bottom 23 thereof. The

sheet is thus wedged against the corner 26 and is,

retained thereby. The bottom 23 of the groove may suitably have a radial width which is either the same or preferably slightly less than the thickness of the sheet In so that the sheet may be additionally retained by the frictional contact with the walls of the groove. The sheet I is thus capable of at least temporary retention in the spiral groove 20 of the plate M, In the operation of my process successive portions of the lower edge of the sheet are retained temporarily by" the grooves until successive points of the upper edge are grasped by the slotted pins 3| of the engaging device 22 in a manner to be described.

The spider i3 comprises a central hub through which the tightening bolt |8 passes'and in the under-face of which the recess I is formed. Diametrically opposed legs or extensions 21 may suitably be formed integral with the hub and are provided with apertures 01' perforations, having the upper portions threaded, through which the slotted pins 2| of the engaging device 22 are passed to engage the upper edge of the sheet H] as is clearly shown in Fig. 4. To form the spider I3, I may suitably provide a plate in which the under-face is formed ,with a spiral groove 36 (Fig. 3) coinciding in pitch to the groove in the groove plate H. Segmental portions 28 are cut out from this plate to form the hub and diametrically opposed legs 21 of the. spider. The perforations in the legs 28 are formed in spaced intervals and their axes intersect the grooves on the underface thereof. Hence the perforations, and consequently the engaging devices 22 positioned therein, are so arranged on the legs 21 of the spider that an imaginary spiral line of predetermined pitch will pass through the centers thereof. Thus, the arrangement of the engaging devices 22 is such as to define a spiral line of a pitch coinciding with the pitch of the groove 20in the plate It. The segmental portions 28. are retained for use in the process of manufacturing the spiral sheet for. a purpose to be hereinafter described.

The engaging devices 22 (Fig. 4) comprise an upper threaded stud or bolt 29 and a lower slotted pin 2|. Any suitable means may be employed to connect the bolt 29 and pin 2| so that the bolt will push or pull the pin through the perforations without imparting any turning or twisting movement thereto. In the drawings, I show one means for accomplishing this desired movement as for example a ball 30 formed integral with the pin 2| and a-socket 3| formed integral with the bolt 29 to form a ball and socket joint; however, any

other suitable means, obvious to one skilled in the art, may be employed to accomplish the desired movement of the pin.

The spiral sheet It! may be secured in the retention apparatus in the following manner.

The sheet to be wound into a spiral may be formed of any substantially rigid and flexible ma-. terial such as metal, artificial condensation prodnets of the phenol-formaldehyde or polyhydric alcohol-dibasic acid types such as Bakelite" or "Glypta1, or like materials. Preferably, however, I utilize a sheet made from some suitable metal is supported on the tubular spacer |1.

such as spring tempered steel, stainless steel, or Monel metal preformed into a spiral sheet with a pitch between the successive turns of the sheet larger than the pitch of the groove in the plate M. The preformed spiral sheet is placed on the groove plate It with one edge, designated as the lower edge, opposed to the groove 20 and the spider The assembly is retained in place by the bolt l8 and nut 19. One portion of the lower edge of the spiral sheet is sprung into the groove 20 and the opposed portion of the upper edge is engaged as by the slotted pin 2| urged through the perforatiori in the overlying leg as by the bolt 29. Successive portions of the lower edge of the spiral sheet are sprung into the groove and the corresponding successive opposed edges are engaged by the slotted pins 2| urged through the succeeding legs. This operation is continued until the sheet has been formed into a spiral of the desired pitch and size. As set forth above, the engaging devices 22 pass through the apertures in the legs 21 along a spiral imaginary line of predetermined pitch and accordingly the engaging devices are set as close-- ly as possible along this line in order to provide sufilcient retention for maintaining the sheet in its desired spirally wound form while the thermoplastic material is poured into the spiral passageway.

The assembled device is now formed into a relatively rigid structure as by the tightening 2| of the engaging device 22 define a spiral line that coincides with the groove 20,1 may provide suitable centering means asfor example lugs or extensions 33 and corresponding recesses 34 in the spider l3 and plate M respectively.

The assembled relatively rigid spiral sheet is now ready to receive the thermoplastic material. The thermoplastic material, in liquefied form, may be poured directly into the spiral passageway between the successive turns of the sheet I0; however, I prefer to employ an additional precautionary measure to assure the maintenance of the desired pitch of the spiral while the thermoplastic material is being poured and while it sets. For this purpose, I make use of the segments 28 cut from the spider sheet as heretofore 0 described. These segments have grooves 36 in the under-face which coincide in size, shape and pitch with groove 20. The grooves 36 of the segments 28 are now pressed ontothe top edges of the spirally wound sheet- In lying between the legs 21 of the spider l3, Fig. 3. It is obvious that the individual segments 28 must be positioned in the same position in relation to the legs' 21 that they-occupied before the legs 21 were formed,

so thatthe underlying groove 36 will coincide with the groove 20 in plate l4. Each of the segments may be provided 'with suitable openings through which the molten thermoplastic material may be poured to fill the spiral passageway between the successive turns of sheet I, although this is not necessary as the thermoplastic may be poured through a single opening in only one as by heat or suitable solvent for the thermo- The thermoplastic can be then removed from the spiral passageway in any desirable manner plastic material. Although I have set' forth above that wax is the thermoplastic material I employ, it is obvious that any other suitable and well-known thermoplastic material, having sufllcient adhesiveness when set, can be used. For example, any of the well-known plasticrubber isomers or cellulose derivatives can be used in lieu of the wax.

While Figs. 1-4 show two sheets wound in spiral form, I have described only one sheet together with the process of winding and forming it and the apparatus required to perform such process. It is obvious that the operations with respect to the second sheet are duplications of those described in connection with the first sheet. By means of my process and apparatus I can suitably form sheets up to 300 feet or more in length into spirals having the desired pitch and with clearance between the successive turns say from I12)! t 1/4 below and increased above 3 4" to suit the desired needs.

Although I have shown sheet III as formed into a spiral of constant pitch, it is to be understood that I consider it within the purview of my invention to utilize my apparatus and carry out my process for forming spirally wound sheets of varying pitch. Furthermore, my invention is not to be construed as limited to a spider embodying the use of four legs, as shown in the drawings, as it is obvious that the number of the legs in the spider may be varied to suit the desired need, thus a smaller or larger number of legs may be employed with like results. If the number of legs be increased, say to six or more,

then .the use of the cut-out segmentsmay be. advantageously dispensed with.

The above modifications and others obvious from the drawings and description are included within the scope of my invention and my inven-- tion is not to be construed as limited to the described process and form shown except as such limitations appear in the claims. Myprocess ,comprehends the formation of a spiral in which a sheet may be engaged at a point and the sheet turned about the engaged point and alternatively wherein the engaged point is turned about an axis to wind the sheet into a spiral.

I claim:

1.' In the manufacture of a spiral sheet from a flat substantially rectangular sheet to form a passageway between the successive turns of the sheet comprising, engaging-a. longitudinal edge of thesheet at a point near the end thereof,

winding the sheet about said secured point, en-

' gaging successive points along said edge, said material.

points being so arranged that a'spiralling line,

of predetermined pitch, will pass through the points, simultaneously engaging the other lon- 'gitudinal edge of the spirallywou'nd sheet in a.

spiral groove having a pitch substantiaily'the same as thepitch of the turns ofthe sheet at thesecured edge and substantially filling the passageway of the spiral with a thermoplastic 2. In'the manufacture of a spiral sheetfrom a flat substantially.rectangular sheet toform a;

passageway between the successive turns of the arranged that a spiral line, having substantially Obviously, the clearance differences. between the successive turns may be decreased the same pitch as the pitch of the groove, will pass through the points. i

3. In the manfacture of a spiral sheet from a flat substantially rectangular sheet to form a passageway between the successive turns of the sheet comprising, guiding a longitudinal edge of the sheet in a spiral groove having a predetermined pitch, engaging successive points alon the other longitudinal edge, said points being soarranged that a spiral line, having substantially the same pitch as the pitch of the groove, will 'pass through the points and substantially filling the passageway between the successive turns of the sheet with. a thermoplastic material.

4. In the'manufacture of a spiral sheet from a flat substantially rectangular sheet to form a passageway between the successive turns of the sheet comprising, guiding a longitudinal edge of the sheet in a spiralgroove having a predetermined pitch and simultaneously engaging successive points along the other longitudinal edge, said points being so arranged that a spiral line, having substantially the same pitch as the pitch of the groove, will pass through the points.

5. In the manufacture of a spiral sheet from a flat substantially rectangular sheet to form a passageway between the successive turns of the 6. In an apparatus'forthe manufacture of'a spiral sheet. having a passageway of predetermined pitch between the successive turns of the sheet, a spider having perforations formed therein along a spiral line of predetermined pitch and engaging means removably retained in said perforations.

'1. In an apparatus for the manufacture of a spiral sheet having a passageway of predetermined pitch between the successive turns of the sheet, a spider having perforations formed therein along a spiral line of predetermined pitch and engaging means removably retained in saidperforations, said engaging means comprising a' slotted pin.

' 8. In an apparatus for the manufacture of a spiral sheet having a passageway of predetermined pitch between the successive .turnsof the sheet, aspider having perforations formed'therein along a spiral line of predetermined pitch and slotted pins r'emovably retained in said perfora time. i;

9'.'In an spiral sheet having a passageway of predetermined pitch betweenthe successive turns of the sheet, aspider havingperforations' formed therein along-a spiral line of predetermined pitch, en-

' gaging means removably retained in said perforations; said engaging means being adapted to en-- gage one edge of the spiral sheet, and a plate having aspiral groove therein of predetermined pitch, in which the other'edge of the spiral sheet can be inserted.

10. In an apparatus for the manufacture of a spiral sheet "having a passageway of predetermined pitch between the successive turns of the sheet, a spider having perforations formed thereinaiongaspirailineofpredeterminedpitcb. en-

apparatus'for themanufa'cture of a gaging means removably retained in said perforations, and engaging means being adapted to engage one edge of the spiral sheet, and a plate having a spiral groove therein of predetermined pitch, in which the other edge of the spiral sheet can be inserted, said spiral groove being defined by walls which slope away from the axis of the spiral sheet.

11. In an apparatus for the manufacture spiral sheethaving a passageway of predetermined pitch between the successive turns of the sheet comprising, a rigid plate member, a spiral groove of predetermined pitch in one face of the plate member, said spiral groove being defined by walls which slope away from the axis of the spiral sheet.

12. In an apparatus forthe manufacture of a spiral sheet having a passageway of a predetermined pitch between the successive turns of the sheet comprising a rigid plate member, a spiral groove of predetermined pitch in one face of the *plate member, said spiral groove being defined by wallswhich slope away from the axis of the spiral sheet, the wall of the groove adjacent the axis of the spiral sheet having a greater inclination than the other wall of the groove and the mouth of the groove having a greater axial width than the bottom thereof.

13. In an apparatus for the manufacture of a spiral sheet having a passageway of predeter- Jnined pitch between the successive turns of the jacent the axis of the spiral sheet having a great er inclination than the other wall of the groove and the mouth of the groove greater axial widtl'i than the bottom thereof.

WALTER J. PODBIELNIAK. 

